The invention pertains to an electrical shielding chamber which is used to house electronic equipment when it is desired to protect equipment from external electromagnetic emissions and/or contain electromagnetic emissions from the equipment.
A common application for electrical shielding chambers is in the area of testing of electronic equipment. In such a case, measurements are often desired of electromagnetic emissions from the equipment without the presence of any background external emissions. In other cases, the sensitive nature of the equipment requires that external electromagnetic emission be shielded against. In other cases the operation of the equipment produces unwanted electromagnetic emissions which are intended to be contained by the shielding chamber.
Prior shielding chambers, often known as Faraday cages, have typically been large structures. Often the size of a room, such chambers are made using wire screening, grating, etc, to provide the desired electrical shielding. For certain applications, existing shielding chambers are nonoptimal. In applications such as shielding chambers on ships, spacecraft or aircraft, premiums on weight and space place advantages on a light-weight and compact chamber. Additionally, such advantages may come into play with regard to a wide variety of field testing situations where portability is desired. For field testing, chambers are often jury-rigged from pieces of wire screening.
A computer terminal shielding cover utilizing metallized fabric has been proposed in U.S. Pat. No. 4,785,136. This appears less than adequate for shielding sensitive electronic devices.